LG HT904TA Service Manual page 4

NOTES REGARDING COMPACT DISC PLAYER REPAIRS
1. Preparations
1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode) . These components
are sensitive to, and easily affected by, static electricity . If such static electricity is high voltage, components
can be damaged, and for that reason components should be handled with care .
2) The pick-up is composed of many optical components and other high-precision components . Care must be
taken, therefore, to avoid repair or storage where the temperature or humidity is high, where strong magne-
tism is present, or where there is excessive dust .
2. Notes for repair
1) Before replacing a component part, first disconnect the power supply lead wire from the unit
2) All equipment, measuring instruments and tools must be grounded .
3) The workbench should be covered with a conductive sheet and grounded .
when removing the laser pick-up from its conductive bag, do not place the pick-up on the bag . (This is
because there is the possibility of damage by static electricity .)
4) To prevent AC leakage, the metal part of the soldering iron should be grounded .
5) workers should be grounded by an armband (1M Ω)
6) Care should be taken not to permit the laser pick-up to come in contact with clothing, in order to prevent
static electricity changes in the clothing to escape from the armband .
7) The laser beam from the pick-up should NEVER be directly facing the eyes or bare skin .
Armband
Resistor
Conductive
(1 M Ω)
Sheet
1-3
Resistor
(1 M Ω)